fix unused warning
fix unused warning

Original commit message from CVS:
fix unused warning

jpakkane/gstreamer,ahmedammar/platform_external_gst_gstreamer,ylatuya/gstreamer,centricular/gstreamer,jpxiong/gstreamer,drothlis/gstreamer,centricular/gstreamer,krichter722/gstreamer,Distrotech/gstreamer,Lachann/gstreamer,lovebug356/gstreamer,ahmedammar/platform_external_gst_gstreamer,ensonic/gstreamer,Lachann/gstreamer,surround-io/gstreamer,cablelabs/gstreamer,centricular/gstreamer,mparis/gstreamer,drothlis/gstreamer,ahmedammar/platform_external_gst_gstreamer,collects/gstreamer,jpxiong/gstreamer,mparis/gstreamer,cablelabs/gstreamer,ensonic/gstreamer,lubosz/gstreamer,shelsonjava/gstreamer,centricular/gstreamer,lubosz/gstreamer,ahmedammar/platform_external_gst_gstreamer,collects/gstreamer,justinjoy/gstreamer,cablelabs/gstreamer,shelsonjava/gstreamer,Lachann/gstreamer,drothlis/gstreamer,Distrotech/gstreamer,shelsonjava/gstreamer,ylatuya/gstreamer,StreamUtils/gstreamer,lubosz/gstreamer,magcius/gstreamer,justinjoy/gstreamer,collects/gstreamer,cfoch/gstreamer,krichter722/gstreamer,drothlis/gstreamer,cablelabs/gstreamer,magcius/gstreamer,cfoch/gstreamer,mrchapp/gstreamer,mparis/gstreamer,Distrotech/gstreamer,StreamUtils/gstreamer,surround-io/gstreamer,magcius/gstreamer,magcius/gstreamer,mparis/gstreamer,mrchapp/gstreamer,ensonic/gstreamer,mparis/gstreamer,Distrotech/gstreamer,krichter722/gstreamer,ylatuya/gstreamer,krieger-od/gstreamer,ylatuya/gstreamer,lovebug356/gstreamer,centricular/gstreamer,jpxiong/gstreamer,krichter722/gstreamer,collects/gstreamer,jpxiong/gstreamer,Lachann/gstreamer,lovebug356/gstreamer,shelsonjava/gstreamer,lubosz/gstreamer,surround-io/gstreamer,Distrotech/gstreamer,justinjoy/gstreamer,lovebug356/gstreamer,jpakkane/gstreamer,collects/gstreamer,magcius/gstreamer,mrchapp/gstreamer,justinjoy/gstreamer,cfoch/gstreamer,krieger-od/gstreamer,mrchapp/gstreamer,ahmedammar/platform_external_gst_gstreamer,StreamUtils/gstreamer,krieger-od/gstreamer,drothlis/gstreamer,Lachann/gstreamer,surround-io/gstreamer,ylatuya/gstreamer,ensonic/gstreamer,shelsonjava/gstreamer,jpakkane/gstreamer,cablelabs/gstreamer,cfoch/gstreamer,surround-io/gstreamer,lubosz/gstreamer,krieger-od/gstreamer,krichter722/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,ensonic/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,jpakkane/gstreamer,krieger-od/gstreamer,mrchapp/gstreamer,lovebug356/gstreamer,cfoch/gstreamer,justinjoy/gstreamer